Good news, we agree with you. We're planning to get to a stage where all of the modules within a template can be editable by the sales rep (with a key exception, more on that in a sec).
The experience will be somewhat similar to the experience of editing a website page in the CMS.
There is a key difference though. The sales manager created template in the "qoute templates" section in settings will determine which modules are actually editable by the sales rep.
The point of this is say you have legal copy that needs to always be consistent. The sales manager can then ensure that consistency by locking it down. For notes, or other content in the quote though it may make perfect sense for the sales rep to have full control. So this allows the sales manager to control all of that.
This functionality requires a very significant reworking of how the sales rep UI works, and we want to make sure we get it right. Unfortunately that functionality isn't ready right now in this phase of the beta.
Thank you so much for taking the time to provide this feedback. Seriously, it really helps validate that we're moving in the right direction!